Wind Turbine Payback in Big Stone County, MN
Wind turbine payback in Big Stone County
No. The turbine wears out before it pays for itself.
At 30 m, the height a home turbine tower usually reaches, the wind in Big Stone County, MN averages 6.34 m/s (14.2 mph). A 10 kW turbine there would make about 22,225 kWh a year, worth $3,654 at MN's 16.44¢/kWh. Against an installed cost of about $100,000, that is a payback of 27 years, and the turbine is built to last about 20.
What to do in Big Stone County
A home turbine is not worth buying for savings in Big Stone County unless your spot is far windier than the county average, 7.5 m/s at the hub against 6.34 m/s here. Per kW, solar panels would make about 1,162 kWh a year here against the turbine's 2,223, so get a solar quote first.
What would have to change
- Power would have to cost 22¢/kWh, 1.4 times what MN pays now.
- Or the average wind at the hub would have to be 7.5 m/s instead of 6.34. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MN
Big Stone County is the 420th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in MN is Lincoln County at 6.68 m/s, payback 25 years.
Month by month in Big Stone County
April is the strongest month here, at 6.97 m/s and about 2,203 kWh. July is the weakest, 5.43 m/s and 1,320 kWh, so the best month makes 1.7 times the worst. November to March brings in 43% of the year's output in Big Stone County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.38 m/s | 1,915 kWh | $315 |
| February | 6.46 m/s | 1,770 kWh | $291 |
| March | 6.59 m/s | 2,044 kWh | $336 |
| April | 6.97 m/s | 2,203 kWh | $362 |
| May | 6.71 m/s | 2,117 kWh | $348 |
| June | 6.04 m/s | 1,645 kWh | $270 |
| July | 5.43 m/s | 1,320 kWh | $217 |
| August | 5.46 m/s | 1,337 kWh | $220 |
| September | 6.44 m/s | 1,886 kWh | $310 |
| October | 6.80 m/s | 2,172 kWh | $357 |
| November | 6.55 m/s | 1,951 kWh | $321 |
| December | 6.28 m/s | 1,853 kWh | $305 |
What a taller tower would buy
Measured at 10 m the wind in Big Stone County averages 5.03 m/s; at 50 m it is 7.06 m/s. That gives a shear exponent of 0.211, typical of ordinary open country. Going from 20 m to 50 m takes output from 18,365 to 27,471 kWh a year, 50% more, before counting the extra cost of the taller tower. Why tower height decides it explains the shear behind these numbers.
| Hub height | Average wind | Output | Payback |
|---|---|---|---|
| 20 m | 5.82 m/s | 18,365 kWh | 33 years |
| 30 m | 6.34 m/s | 22,215 kWh | 27 years |
| 40 m | 6.74 m/s | 25,132 kWh | 24 years |
| 50 m | 7.06 m/s | 27,471 kWh | 22 years |
Counties around Big Stone County
5 of the 6 closest counties are windier at turbine height; the windiest, Grant County, averages 6.71 m/s.
- Stevens County, MN: 6.34 m/s, 22,225 kWh, payback 27 years (23 mi)
- Traverse County, MN: 6.37 m/s, 22,447 kWh, payback 27 years (24 mi)
- Grant County, SD: 6.71 m/s, 24,947 kWh, payback 28 years (25 mi)
- Roberts County, SD: 6.62 m/s, 24,289 kWh, payback 28 years (30 mi)
- Lac qui Parle County, MN: 6.39 m/s, 22,595 kWh, payback 27 years (31 mi)
- Swift County, MN: 6.39 m/s, 22,595 kWh, payback 27 years (36 mi)
Sun versus wind in Big Stone County
Big Stone County gets 3.98 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,162 kWh a year; one kW of the turbine above makes 2,223. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.9 times. Panel output assumes an 80% system performance ratio. Wind or solar runs the same comparison for every county.
How this is worked out
Wind is NASA's Power climate record, the 2001-2025 average at 10 m and 50 m for the county's centre, carried to 30 m with this county's own measured wind shear and spread into hours with a Rayleigh distribution. The turbine is a generic 10 kW, 7 m rotor machine with 10% losses. Cost is $10,000 per kW installed with no tax credit, because the federal one ended in 2025. One county-centre number cannot see your hilltop or your tree line, so treat it as the starting point for a site survey, not a substitute. The full method and its weak spots are in how the numbers are made.